Refrigerating apparatus



B. B. HOLMES.

v REFFHGERATING APPARATUS.

APPLICATION FILED FEB.26.1920.-

Y Patented Nov. 21 19220 l It INVENTOR BRADFORD B. HOLMES,

within. Preferably,

Patented Nov. 21, W22.

- Application filed rebmar as, 1920. Serial No. 361,404.

To all whom it may camera:

Be it known that I. Bnaoronu B. Holmes, a citizen of the United States, and resident of New York city, in the county of New York and State of New York, have invented cer-s tain new and useful Improvcmentsin Refrigerating Apparatus, of which the following is a specification.

Iy present invention relates to refrigeratmg apparatus of the type wherein a volatile liquid is evaporated to absorb heat thereby producing the desired refrigerating efiect, the volatilized gas is rc-liquefied by compression andfilcooling, and the condensedv liquid is returned to theevaporating chamber to be again evaporated, in continuously regeating cycle.

he arrangement joints are around relatively large openings and these are closed by relatively massive parts having ample contact surfaces rigidly bolted together so that, with the low pressures employed, development of leaks is practically impossible. Moreover, an important feature of my invention is a novel arrangement for transmitting power from the exterior motor to the compressor through a wall of'the condensing chamber, without using any stufling box or packed joint such as is commonly employed to prevent leakage where there is a rotary shaft or other driving element having moving engagement with an opening through the wall of a pressure chamber. I

I accomplish this by employing a flexible closure secured gas-tight over an opening through the wall of said condensing chamher. Secured gas-tight in a movable portion of said flexible closure is a power transmitting member the power transmitting movements of which flex said closure but do not require rotation of said member.

I employ a flexible tubular member which will give suflicient resistance againstthe internal gas pressure and against any tendency to be rotated by the ii for the tubular member motion transmitting device. Ifvery flexible,

the tubular member will be extended out side of the condensing chamber so as tobe distended by the gas pressure applied from however, it will be of suflicient radial stifl'ness to withstand the pressure when appliedon the outside therethe tube may project The latter arol,and, in such case, into the condensing chamber.

is such that the only maybe .of any fording the required power-one-quarter 11o rangement is of advantage since a tube-stiff enough to withstand the external pressure must usually be quite long-in order to have suiiicient lateral flexibility.

The flexible tubewhich I prefer to use for this purpose is a well known form of thin metal tubing having deep flat-sided corrugations. These corrugations may be circular as in tubes now obtainable in the market or they may manner of a screw-thread of slight pitch.

be helically disposed after the 5 Where considerable pressures are employed and particularly where the tube is of considerable length as in my present device,

internally applied pressure operates to pro- 7 duce unequal, longitudinal curvature of the walls thereby subjecting the metal of the walls to undesirable initial tension stresses on one side of the tube and corresponding compression stresses on the other side, where- 7 as, externally applied pressure tends to straighten the tube if curved and to resist Hence, there is peculiar utility and advantage in'employing this type of flexible tube as a flexible closure projecting into the condensing chamber rather than outwardly therefrom.

In vorder that the crank shaft may be properly supported within the flexible tube,

prefer to arrange sleeve projecting from a plate which may be bolted over the opening around which the flexible tube is clamped and sealed as above described.

The above and other vention may be more fully understood from the following description in connection with the accompanying drawings, in which Figure 1 is a vertical section along the axis of the machine;

Fi ure 2 is a cross section on A- ,Figure 1;

Figure 3 is a perspective sketch of the motor and vanes of the compressor; and

Figure 4 is a sectional detail ed form of crank transmission.

In Figure 1 the device is'shown as mounted on, a portion of arefrigerator 10 which of any known or desired construction. which'may be a metal casting on which is rigidly mounted the electric motor 12 and a condenser chamber 13. The motor may be known or desired construction afan overhung bearing features of my into as the line of a modiice The mounting comprises a base 11 horse power or more according to the size of the machine; The condenser 13 is a casting preferably of copper so as to be of high heat conductivity. otherwise provided with numerous longitudinal ribs 14, projecting from its outer surface. It is preferably surrounded by a casing 15 which may be of sheet metal and which preferably contacts with the outer edges of the ribs to form longitudinal passages for flow of the cooling air. An air draft through these passages is maintained by fan 16 on the shaft of motor 12 thus coolin the condenser.

ithin the condenser and attached to the end plate 17 is the compressor. This is preferably a rotary force pump comprisingthe rotor 18 and-blades 19 which revolve within the hardened steel cylinder 20 and the end plates 21 and 22 which carry the ball bear ings on which the rotor revolves. The blades 19 are of hardened steel and contain grooves 23 on their side edges. The slots'in the rotor 18 into which the blades fit are machined clear through so that the rotor'consist's of 4 separate quarter cylindrical elements held I together by the shoulders 24.

pistons div ding the Casing 20 contains a suction port 28 which communicates with space 26 in the evaporator 29 by the passage'30 shown in dotted lines; also a discharge port 31 which discharges into the condenser 13 in such a manner that the compressed gas containing a small amount of glycerine which has leaked by the clearances in the pump, is blown out through ball bearings 32 and 33, serving to lubricate them.

The blades 19 are yieldingly pressed outward against the inner surface of casing 20 by centrifugal force and are in effect rotary ump cylinder in four chambers of cyclically increasing volume, sucking gas on the increase of volume and compressing it on'the decrease in the well known way.

A small hole 25 is drilled lengthwise through the outer shaft of the pump and communicates with the evaporator space 26 and also by passage 27, with the bottom of the condenser. The condenser contains a certain amount of glycerine for lubricating purposes, and owing to the fact that when the pump is in rotation, the axial space is under less pressure than exists in the condenser, theglyeerine will be forced via passages 27, 26, and 25 into therotor of the pump where it will seal the clearances between blades 19 and rotor 18, fill grooves 23 and generall act as a lubricant for the pump and a iquid seal on the pump clearauces.

It will be noted that the entire pump assembly can readily be removed from the t is cast, machined, or

pum in the following manner. A plate 34 is bo ted gas tight to the condenser 13 oppoor other flexible composition or the plate 34 could be made as a flexible diaphragm. I prefer to use, however, the flexible circularly or helically convoluted tube which is an article in general use. At the inner end this tube is sealed gas-tight to the non-rotating. owertransmitting member 36. The shaft 3' has a crank 38 at its end, the centerline of the crank being along the line B B. Rotation of the shaft 37 and crank 38 transmits topiece 36 through the ball bearing 39 the above described non-rotating circular motion which for want of a better name may be called oscillatory.

Piece 36 has crank 40 attached to it which movingin a circle, transmits rotary motion to the pump shaft crank 41 by means of the ball bearing 33. It is clear that member 36 has no tendency to rotate except that due to friction of the cranks and this is resisted by tube 35 which is secured to plate 34.' Member 36 will oscillate however and axis BB of this oscillation is designed so that the tube is subjected to a natural and simple bending very slight inamount and only a fraction of the elastic limit of the tube. 4

The arrangement of the crank pins and sockets in different transverse planes as shown in Figure 1 involvesa certain amount of twisting strain and resulting friction between the member 36 and the rotating crank elements which, if desired, may be avoided by arranging these parts concentrically so that they transmit power in the same transverse plane as shown in Figure 4. In this figure, the driving crank pin 38 engages the member 36ir'1side of and concentrically with the crank stud 40 which latter is encircled by the crank socket 41 concentric therewith. If desired the eccentricity of the rotating load on the crank may be counterbalanced by eccentric weights 50 and 51 on the respectlve driving and driven shafts. It will be obvious that the relation of crank pins and sockets may be reversed or varied if desired and in any case, the rotary crank axes may be made parallel with the shaft axis provided a double curve for tube 35 is found unobjectionable.

It is obvious that oscillation of piece 36 ing motion may be changed to rotary motion by external and internal gears or many other means, or to reciprocating motion in case it is desired to use a, reciprocating pump instead of a rotary pump. 4

' the pump in small denly Shaft 37 is connected to the motor by the friction clutch 42 which may be any suitable form of friction clutch. The primary purpose of this is to limit the pressure in the condensing chamberas hereafter explained. It will be noted, however, that tube 35 is sub- )QCtGd to the torque due to crank pins, and clutch 42 will prevent an excessive strain such as might be develops as for instance, if some part of the mechanism should jam, or if the pump should sudsuck a large quantity, of liquid instead of gas.

The evaporator 29 is a copper vessel bolted to the condenser 13 and base casting 11, forming a unit with them.- It contains the float 43 actuatin the inlet valve 44 whereby fresh liquefied re rigerant is admitted to take the place of that evaporated. The refrigerant is preferably ethyl chloride. The 'float, which in this case is shown of cork, but may be constructed in other ways, has its buoyancy so proportioned to the size of the valve 44 that flotation will close the valve 44 against any usual pressures in the condenser, but not against an abnormal pressure. This valve thus becomes also a safety valve preventing any excessive pressure from generating in the condenser and eliminating the necessity of a pressure switch to cut out the motor. I T

Owing to the fact that normally, even when the machine is idle, the pressure in the evaporator is less than in the condenser, glycerinewill from time to time flow from quantities to the evapmust, therefore, be made for returning this glycerine to the condenser. Thi is accomplished by providing a. second float, 45, which is of buoyancy proportioned to its load so that it floats in glycerine but sinks, in the liquid ethyl chloride. This fioat carries the tube 46 open at the bottom and orator. Provision entering the exhaust port 47. As glycerine accumulates it raises this float forcing the tube 46 further into the port 47 thereby throttling the suction on the gas until glycerine is sucked through the suction pipe into the pump and discharged into the condenser.

The refrigerating machine is-attached to any suitable, refrigerator 10 by cutting a hole in the top of the refrigerator through which the evaporator 29 pro ects. A brine tank 48 may be then slipped over the evaporator and held in place by the bayonet catch and slot 49. While the machine may be operated without the brine tank a more even temperature can be maintained in the ice box by its use as the brine upplies a reserve of cold to more quickly compensate the temperature when doors are opened, etc. A compartment 50 may be provided for the reception of trays containing water to be frozen.

A thermostatic electric switch (not shown as it is common in the controls the the friction of the 1 motor starting it when the temperature in the box gets too high and stopping it when compressed in the pump and becomes heated.

It is discharged hot and under pressure into the condenser where its heat is absorbed by the air cooled condenser walls and it'liquefies, settling into the bottom of the condenser, and overflowin into the evaporator where it is again available forevapora-tion as beore;

Other refrigerating agents and other lubricants can be used instead of ethyl chloride,

and glycerine as can other materials in the construction of the device. Likewise the transfer of power to within the enclosed vcsselmay be effected in many other ways than that shown in the preferred form. I therefore do not limit myself to the construction here shown but reserve the right to embody this invention in any other way which lies within the spirit of the invention and the scope of my claims.

While the apparatus may be constructed of any desired ity, it will be found that one somewhere around twice the dimensions shown in the size and refrigerating capac-' original drawings forming' part of this ap u plication will be of sufiicient capacity for an ordinary small refrigerator. In such a device the motor may be about a quarter horse power rotating say 1700 revolutions per minute. The axis of the crank pins for transm'itting the power from the motor to the compressor may, have an eccentricity of say three-eighths inch giving a crank throw of three-quarters inch. Withethyl chloride as the refrigerant, the pressure maintained in the condenser may be about 40 pounds, float 43 and valve 44 being designed to withstand substantially. that pressure. At such pressure the ethyl chloride will condense at about 130 Fahrenheit, thus giving a reasonable temperature drop and efiective cooling for the outside air even in hot summer weather. The friction coupling 42 may be set to slip when the internal pressure against which the pump works is considerably above the working pressure of 40 pounds, the load required for slip being in such case a back I seams and openings &

immovableduring operation of the device and one of said closures being flexible; said container comprising interiorly an evaporating chamber and a condensing chamber with interiorly commuliicating conduits for circulation of fluid, one of said conduits being for flow of fluid from the evaporating chamber to the condensing chamber and another conduit for return of fluid from the condensing chamber to the evaporating chamber, in combination with a compressor pump located in the condensingchamber having its intake through said suction conduit, means for actuating said pump by non-rotary motion of a. movable element carried by said flexible closure, an outlet valve located in said return conduit controlled by the buoyancy of a float in the vaporizable liquid'in the evaporating chamber so as to vent the condensing chamber into the evaporating chamber when the pressure in the former exceeds a predetermined limit, and means for driving the compressor including a friction coupling adapted to slip in case the resistance and back pressure on the compressor becomes abnormally high.

2-. An evaporating and condensing system for a volatile liquid, comprising a container having all ekterior seams and openings efitted with closures secured gas-tight by sealed joints between surfaces which are int-- movable duringcperation of the device and one of said closures being flexible; said container comprising interiorly an evaporating chamber and a condensing chamber with interiorly communicating conduits for circulation of fluid. one of said conduits being for flow of fluid from the evaporating chamber to the condensing chamber and another conduit for return of fluid from the condensing chamber to the evaporating chamber, in combination with a compressor pump located in the condensing chamber having its intake through said suction conduit, means for actuating said pump by nonrotary motion of a. movable element car-- ried-by said flexible closure, an outlet valve located in said return conduit controlled by the buoyancy of'a float in the vaporizable liquid in the evaporating chamber so as to vent the condensing chamber into the evaporating chamber when the pressure in the former exceeds a predetermined limit.

3. An evaporating and condensing system for a volatile liquid, comprising a, container having all exterior seams and openings closed by sealed joints between surfaces which are relatively immovable during operation of'the device, said container comprising interiorly an evaporating chamber and a condensing chamber'with interiorly communicating conduits for circulation of fluid, one of said conduits being for flow of fluid from the evaporating chamber to the condensing chamber and another conduit for return of fluid from the condensing chamber to the evaporating chamber, a rotary compressor located in the condensing chamber'havingits intake through said suction conduit and an outlet valve located in said return conduit controlled by the buoyancy of a float in the vaporizable liquid 1n the evaporating chamber adapted ,to vent the condensing chamber into the evaporating chamber when the pressure in the former exceeds a predetermined limit.

4. An evaporating and condensing system for a volatile liquid, comprising a container having all exterior seams and openings closed by sealed joints between surfaces which are relatively immovable during operation of the device, said container comprising interiorly' an evaporating chamber and a condensing chamber with interiorly communicating conduits for circulation of fluid, one of said conduits being for flow of fluid from the evaporating chamber to the condensing chamber and another conduit for return of fluid from the condensing chamber to the evaporating chamber, a rotary compressor located in the condensing chamber having its intake through said suction conduit and an outlet valve located in said return conduit controlled by the buoyancy of a float in the vaporizable liquid in the evaporating chamber adapted to vent the condensing chamber into the evaporating chamber when the pressure in the former exceeds a predetermined limit, in combination with means for driving the compressor including a friction coupling adapted to slip in case the resistance and back pressure on the compressor becomes abnormally high.

5. A refrigerating apparatus comprising an evaporating chamber, a condensing chamber, a compressing pump, having conduit connections for sucking fluid from the evaporating chamber and compressing it in the condensing chamber, an overflow return conduit from the condensing chamber to the evaporating chamber, a supplemental suction conduit for drawing lubricating liquid from the bottom of the condensing chamber into the compressor and means for drawing lubricating fluid from the bottom of the evaporating chamber to the main intake of the compressor, said means comprising a valve having a tubular stem adapted to variably throttle the intake of said main suction conduit, the lower end of said tubular stem being in communication with the bottom of the evaporating chamber and a float adapted to lift said tube and valve to increase throttling of the suction intake when the lubricant in the evaporating chamber exceeds a predetermined depth.

6. A refrigerating apparatus comprising an evaporating chamber, a condensing chamber, a compressing pump and suction conduit for pumping vaporized refrigerant from the evaporating c race, ea

from the evaporating chamber to the condensing chamber and a valve controlled passage for return of fluid to the evaporating chamber, in combination with means for applying non-volatile lubricating spray to the intake of said pump, said means comprising a valve having a perforated stem pro ecting into the suction passage leading from the evaporatin chamber to the compressor and having its ower and extending into a body of fluid lubricant.

7. A refrigerating apparatus comprising an evaporating chamber,a condensing chamher, a compressing pump and suction conduit for pumping va orized refrigerant amber to the condensing chamber and a valve controlled passage for return of fluid to the evaporating chamber, in combination with means for applying non-volatile lubricating spray to the intake of said pump, said means comprising a valve having a perforated stem projecting into the suction passage leading from the evaporating chamber to the compressor and having its lower end extending nto a body of fluid lubricant, and means controlled by the level of the lubricant to vary the degree of throttling of said suction passage by said valveand tubular stem.

8. A refrigerating apparatus comprising an evaporating chamber, a condensing chamber, a compressor'located in said condensing chamber, and suitable conduit connections for pumping evaporated refrigerant from the trolled passage for return of fluid to the evaporating chamber, in combination with a motor outside said chamber and means for transmitting power from the outside motor to the interior compressor, said means meluding a power shaft extending freely through an opening in a Wall of the condensing chamber, and means for transmitting the rotary motion oi said motor shaft to the compressor shaft, said means including an imperforate power transmitting member, means on the motor shaft for driving said intermediate member in a circular path without rotating it and a flexible closure for sealing said imperforate member over sa d shaft opening and over the portion of sold shaft extending inside said wall through said .openin o r 9. A refrigerating apparatus comprising a suitable support, a container for the refrigerant secured to and depending fromsaid support, a cooling and condensing chamber secured to the upper side of said support having cooling pro ections on the outside surface thereof and an outside wall enclosing the same to form longitudinal passages for the cooling air, an electric fan motor at one end of said cylinder, and walls for said condensing chamber comprig plates secured gastight on the ends thereof,

ormer to the latter and a valve con-.

a compressor mounted on the inner face of one of said plates, power transmitting means mounted in and extending from the inner face of the opposite plate including suitable bearings formed on said plate, a rotatable shaft mounted in said bearings and extending through an exterior opening in said plate and a gas-tight closure for said exterior opening and shaft, said closure including a flexible element and an transmitting member secured gas-tight to a movable portion of said flexible element, means on the driving shaft engagin an outwardly presented portion of" sai transmitting member to move the same without rotating it, and means on the compressor shaft engaging an inwardly presented portion of said member to be rotated by the non-rotary movement of the latter.

10. A refrigerating apparatus comprising a suitable support, a container for the refri rant. secured to and dependin sai support, a cooling and con ensing chamber secured to the upper side of said support having coolin projections on the outside surface thereo and an outside wall enclosing the same to form longitudinal passages for the cooling air, an electric fan motor at one end of said cylinder, end walls for said condensing chamber comprising plates secured gas tight on the ends thereof, a compressor mounted on the inner face of one of said plates, power transmitting means mounted in and extending from the inner face of the opposite plate including suitable bearings formed on said plate, a rotatable shaft mounted in said bearings and extending through an exterior opening in said plate and a gas-tight closure for said exterior opening and shaft, said closure including a flexible element and an imperforate gas-tight to a movable portion of said flexible element, means for applying the ower ofthe motor to an outwardly resente portion of said member to move t e same without rotating it and means engaging an in- Wardly presented portion of said member for actuating said compressor.

11. An evaporating chamber and a condensing chamber-containing a body of ii uid refrigerant and also a body of liquid in ricant of ater specific gravity than said refrigerant, in combination witn means for pumping fluid from the evaporating chamher into the condensing chamber; a valve controlling the passage for return flow of fluid from said condensing chamber to said evaporating chamber; and a throttle element having a tubular stem adapted to project into and variably throttle the suction passage to the compressor at one end and having its inlet end below the lubricant and a float having its buoyancy proportioned to its load so that it floats upon imperforate power powerfrom I power transmitting member secured level of said and is controlled by the level of said lubricant. a

12. An evaporating chamber and acon densing chamber containing a body of liquid refrigerant and also a body of liquid lubricant of greater specific gravity than said refrigerant, in combination with means for pumping fluid from the evaporating chamber into the condensing chamber; a valve controlling the passage for return flow of fluid from said condensing chamber to said evaporating chamber; a float buoyed by the refrigerant and having its lifting power said lubricant and a float having its buoy- .ancy proportioned to its load so that it floats upon and is controlled by the level of said lubricant.

13. A chamber containing gas hermetically sealed against escape to the exterior air, and exterior and interior mechanisms, one driving and the other driven thereby, in combination with means for transmitting motion between said mechanisms through a wall of said chamber, said means including a shaft having one end extended inwardly through an opening in the chamber wall and provided with a crank on the inner end thereof, a crank on the shaft'of said interior mechanism in alignment with said first mentioned crank, an imperforate, non-rotating member for transmltting the motion of said shaft, and a flexible tube secured gas-tight over said shaft opening .and also to said intermediate member, the

axis of. the aligned crank pins being inclined to the axis of the shafts on which they are mounted and the plane of the intermediate member correspondingly inclined so that said flexible tube bends 'bv the continuous curve in one direction from the fixed to the movable end thereof.

14. A chaniber containing gas hermetically sealed against escape to the exterior air, and exterior and interior mechanisms, one driving and the other driven thereby,

in combination with means for transmitting motion between said mechanisms through a wall of said chamber, said means including a shaft having one end extended inwardly through an opening in the chamber wall and provided with a crank on the inner end thereof, a crank on the shaft of said v interior mechanism in alignment with said first mentioned crank, an imperforate, nonrotating member for transmitting the mo-,

tion of said shaft and a deeply corrugated thin metal tube encircling said shaft and one end around sai shaft opening and the being inclined to the axis of the shafts on which they are mounted and the plane of the intermediate member correspondingly inclined so that said flexible tube bends by the continuous curve in one direction from the fixed to the movable end thereof.

15. In an apparatus utilizing cyclic expansion and compression of a gas, including a gas containing chamber, a compression chamber and means for transmitting power through a wall of said apparatus, said means including a deeply corrugated thin metal tube having oneend secured gastight around an opening in the wall of said compression chamber, and an imperforate non-rotating power transmitting member secured gas-tight in the other end of saidtube.

16. In an apparatus utilizing cyclic expansion and compression of a gas,'including a gas containing chamber, a compression chamber, a pressure translating mechanism located in one of said chambers and conduits for flow of fluid in a cyclic path through said gas containing chamber, mechanism and compression chamber; and means fdr transmitting power through a vwall of said apparatus, said means including a non-rotatm'g flexible member secured gas-tight over an opening through said wall.

sion chamber, a pressure translating mechanism located in one of said chambers and conduits for flow of fluid in a .cyclic path through said gas containing chamber, mechanism and compression chamber; and means for transmitting power through a wall of said apparatus, said means including a deeply corrugated thin metal tube having one end secured gas-ti ht around an opening in' the wall of sai compression chamber, and an imperforate non-rotating power transmitting member secured gas-t1 ht in the other end ofsaid tube.

18.- u an apparatus utilizing cyclic expansion and compression of'a gas, including a gas containing chamber, a compression chamber and means for transmitting power through a wall of said apparatus, said means. including a non-rotating flexible member secured gas-tight over an opening through said wall.

19. An apparatus for compressing gas including a gas containing chamber, a comT- pression chamber, a compression mechanism \located in one of said chambers and convother end to said intermediate'member, the axis of the aligned crank pins tenet compression mechanism and said compressionv chamber; and means for'traitting motion between the interior and exterior of said apperatus said means including a nonrotating flexible member seated gestight over an o ening through a weil of one of said chamhers.

20. An apparatus for compressing gas including a. gas containing chamber, 2:: compression chem-heme compression mechanism located in one of said chambers and conduits for flow of fluid in e cyclic path through said gas conteinin chamber, said" compression mechanism en seid compression chamber; and means for transmitting motion between the interior and e rior of said vapparatus, said me including a deeply corrugated thin metni tube having one end secured gas-ti ht around an opening in the well of sci compression chember, and en imperforete non-rotating power transmitting member secured gas-tight in the other end of said tube.

21. In at power treitting joint for gas compressors, the combination of a pining; a motor; s driving connection between t e motor end the pump comprising e joint; :1 bellows diaphragm sealing the joint; and a movable member extending from the motor through the diaphragm to the pump for conveying the movement of the motor to the pump; the bellows being arranged to end toward the high pressure side of the joint so that the compression takes efiect on the exterior of the bellows, for the purpose described.

pm at New York city in the county of' York and State of New York this dny of Februer A. D. 1920.

BRA FORD B. HULMES. 

